Fixed bug in long masking ops.

diff --git a/Objects/longobject.c b/Objects/longobject.c
index 37f2f3529b0e9f89b2adaa8373fd79de7fed4dc5..b21738de6e005ffd1386b645cb4b80277f49c8dd 100644 (file)
--- a/Objects/longobject.c
+++ b/Objects/longobject.c
@@ -1145,6 +1145,9 @@ long_lshift(a, b)
        return (object *) long_znormalize(z);
 }
 
+#define MAX(x, y) ((x) < (y) ? (y) : (x))
+#define MIN(x, y) ((x) > (y) ? (y) : (x))
+
 /* Logical or the absolute values of two long integers.
    The second value is first xor'ed with 'mask'. */
 
@@ -1155,22 +1158,23 @@ x_or(a, b, mask)
        int mask;
 {
        int size_a = ZABS(a->ob_size), size_b = ZABS(b->ob_size);
+       int size_max = MAX(size_a, size_b);
+       int size_min = MIN(size_a, size_b);
        longobject *z;
        int i;
        
-       /* Ensure a is the larger of the two: */
-       if (size_a < size_b) {
-               { longobject *temp = a; a = b; b = temp; }
-               { int size_temp = size_a; size_a = size_b; size_b = size_temp; }
-       }
-       z = alloclongobject(size_a);
+       z = alloclongobject(size_max);
        if (z == NULL)
                return NULL;
-       for (i = 0; i < size_b; ++i) {
+       for (i = 0; i < size_min; ++i) {
                z->ob_digit[i] = a->ob_digit[i] | (b->ob_digit[i] ^ mask);
        }
+       /* At most one of the following two loops executes */
        for (; i < size_a; ++i) {
-               z->ob_digit[i] = a->ob_digit[i] | mask;
+               z->ob_digit[i] = a->ob_digit[i] | (0 ^ mask);
+       }
+       for (; i < size_b; ++i) {
+               z->ob_digit[i] = 0 | (b->ob_digit[i] ^ mask);
        }
        return long_znormalize(z);
 }
@@ -1185,22 +1189,23 @@ x_and(a, b, mask)
        int mask;
 {
        int size_a = ZABS(a->ob_size), size_b = ZABS(b->ob_size);
+       int size_max = MAX(size_a, size_b);
+       int size_min = MIN(size_a, size_b);
        longobject *z;
        int i;
        
-       /* Ensure a is the larger of the two: */
-       if (size_a < size_b) {
-               { longobject *temp = a; a = b; b = temp; }
-               { int size_temp = size_a; size_a = size_b; size_b = size_temp; }
-       }
-       z = alloclongobject(size_a);
+       z = alloclongobject(size_max);
        if (z == NULL)
                return NULL;
-       for (i = 0; i < size_b; ++i) {
+       for (i = 0; i < size_min; ++i) {
                z->ob_digit[i] = a->ob_digit[i] & (b->ob_digit[i] ^ mask);
        }
+       /* At most one of the following two loops executes */
        for (; i < size_a; ++i) {
-               z->ob_digit[i] = a->ob_digit[i] & mask;
+               z->ob_digit[i] = a->ob_digit[i] & (0 ^ mask);
+       }
+       for (; i < size_b; ++i) {
+               z->ob_digit[i] = 0 & (b->ob_digit[i] ^ mask);
        }
        return long_znormalize(z);
 }
@@ -1208,36 +1213,34 @@ x_and(a, b, mask)
 /* Logical xor the absolute values of two long integers.
    The second value is first xor'ed with 'mask'. */
 
-static longobject *x_and PROTO((longobject *, longobject *, int));
+static longobject *x_xor PROTO((longobject *, longobject *, int));
 static longobject *
 x_xor(a, b, mask)
        longobject *a, *b;
        int mask;
 {
        int size_a = ZABS(a->ob_size), size_b = ZABS(b->ob_size);
+       int size_max = MAX(size_a, size_b);
+       int size_min = MIN(size_a, size_b);
        longobject *z;
        int i;
        
-       /* Ensure a is the larger of the two: */
-       if (size_a < size_b) {
-               { longobject *temp = a; a = b; b = temp; }
-               { int size_temp = size_a; size_a = size_b; size_b = size_temp; }
-       }
-       z = alloclongobject(size_a);
+       z = alloclongobject(size_max);
        if (z == NULL)
                return NULL;
-       for (i = 0; i < size_b; ++i) {
+       for (i = 0; i < size_min; ++i) {
                z->ob_digit[i] = a->ob_digit[i] ^ (b->ob_digit[i] ^ mask);
        }
+       /* At most one of the following two loops executes */
        for (; i < size_a; ++i) {
-               z->ob_digit[i] = a->ob_digit[i] ^ mask;
+               z->ob_digit[i] = a->ob_digit[i] ^ (0 ^ mask);
+       }
+       for (; i < size_b; ++i) {
+               z->ob_digit[i] = 0 ^ (b->ob_digit[i] ^ mask);
        }
        return long_znormalize(z);
 }
 
-#define MAX(x, y) ((x) < (y) ? (y) : (x))
-#define MIN(x, y) ((x) > (y) ? (y) : (x))
-
 static object *
 long_and(a, w)
        longobject *a;